Optimization algorithms and cyclic designs

Optimization algorithms perform well in many construction problems. We describe several algorithms used in recent research on designs. These include algorithms for generating cyclic 2-designs, studying the number of mutually disjoint cyclic designs (with application in the search for large sets of designs) and constructing super-simple designs.     

Four New Stilbene Oligomers in the Root of Gnetum gnemon

Four new stilbene oligomers, gnemonols G, H, I, and J ( 1 – 4 ), were isolated from acetone extract of the root of Gnetum gnemon along with five known stilbenoids, ampelopsin E, cis‐ampelopsin E, gnetins C, D, and E. The structures were elucidated on the basis of spectroscopic evidence.     

Stability of periodic traveling waves for complex modified Korteweg-de Vries equation

We study the existence and stability of periodic traveling-wave solutions for complex modified Korteweg-de Vries equation. We also discuss the problem of uniform continuity of the data-solution mapping.     

Anionic polymerization and copolymerization in heterogeneous systems on surfaces with aromatic structure

Methacrylaldehyde, methyl methacrylate, methacrylonitrile, styrene and isoprene readily polymerize on potassium–graphite inclusion compounds in ethereal and hydrocarbon solvents. The structure of polymethacrylaldehyde, poly(methyl methacrylate), and polyisoprene as well as the composition of styrene–acrylonitrile and styrene–isoprene copolymers have been investigated. The copolymers have a high content of styrene units which is interpreted in terms of selective adsorption of styrene on the initiator surface.     

Occurrence of Stilbene Glucosides in Upuna borneensis

Four new stilbene glucosides, upunosides A ( 1 ), B ( 5 ), C ( 6 ), and D ( 7 ), were isolated from the stem of Upuna borneensis (Dipterocarpaceae) together with the three known glucosides 3, 4 , and 8 . Upunoside A ( 1 ) is the first natural instance of a glucoside of a resveratrol pentamer, and its aglycone has a dibenzo‐fused bicyclo[5.3.0]octadiene and two dihydrobenzofuran moieties. The relative structure of the aglycone was determined by spectral analysis including 1D and 2D NMR experiments.     

On the algebraic curves for circular and folded strings in AdS5×S5

There have been recent advances in the construction of algebraic curves for certain classes of string solutions in the context of the AdS/CFT correspondence. In this paper we obtain the Lax operators and associated spectral curves for circular and folded string solutions in AdS ${}_5\times S^5$. In addition, we provide an original approach for the reconstruction of string solutions in S³ from their corresponding curves.     

Entropy Function Approach to the Lattice Boltzmann Method

In this paper, we present the construction of the Lattice Boltzmann method equipped with the H-theorem. Based on entropy functions whose local equilibria are suitable to recover the Navier–Stokes equations in the framework of the Lattice Boltzmann method, we derive a collision integral which enables simple identification of transport coefficients, and which circumvents construction of the equilibrium. We discuss performance of this approach as compared to the standard realizations.     

Resveratrol derivatives from Upuna borneensis

Four new resveratrol derivatives, upunaphenols B (1), C (4), D (5) (resveratrol tetramer) and E (6, resveratrol dimer with a C6-C1 unit), together with nine known resveratrol oligomers and resveratrol were isolated from an acetone soluble part of stem of Upuna borneensis (Dipterocarpaceae). The structures of new compounds were determined by spectral analysis including 1D and 2D NMR experiments.     

Projective two-weight codes with small parameters and their corresponding graphs

Projective two-weight codes with relatively small parameters are enumerated up to equivalence. Some properties of codes and related strongly-regular graphs are presented. I. Bouyukliev was partially supported by the Bulgarian National Science Fund under Contract MM1304/2003. J.Winne thanks the Fund for Scientific Research—Flanders (Belgium) for a Research grant.